Miscalculation of closing numbers, 1.5 years after the fact

[Roee Agami]

Bought a property in MA on December 2018. The closing included the seller providing credit for the tenants deposit checks.

Now I have my first tenant leaving and looking at his lease, I see that he paid last month up front. Examined the rest of the leases and one other tenant had this in his lease as well (total of 1800$).
I was not credited by the seller for these amounts (verified in the CD).

1. Who's fault is it? Mine? The closing attorney?
2. Anything I can do now about it? So long after closing?

Tried contacting my closing attorney, but as soon as I got to ask what can be done about it, he disappeared not returning my calls or emails (maybe he realized it's his fault and doesn't want to take the blame?).

Contacted the seller as well, which said she'll check with her attorney, but never got back to me.

Thanks.